I'm consistently getting this error (Ubuntu report a problem) after boot:
MythTV Backend Setup has closed unexpectedly
I thought it may be MythTV Backend, and a "race" situation, network not up or capture device not up, but
there is that word Setup in the error. The backend is running, but that could be because it restarted after failure.
So, I modified the service:

Need some more info. The error message doesn't exist in the current MythTV code base.

Where does it show up (journal/syslog/mythbackend.log etc.)

It could be that its from a *buntu product.

A link to the "Error report" may help as the above refers to a mythcommflag assert
and nothing to do with mythtv-setup.

See if the ExecStart=/usr/bin/mythbackend file is an executable or a shell script
that ends up executing mythbackend.real (that used to be a Mythbuntu solution.)
And see if it, for some reason, tries to start mythtv-setup or mythtv-setup.real.

funny thing... it has not happened since the second reboot. Could it have been a background job, flagging commercials that failed?
It was happening everyday soon after boot. I'm gonna take out the sleep and see what happens.

after a really long time (of no errors) the error came back. I really think it has something to do with jobs in the queue being run after startup. It's mythcommflag jobs, which are set to run automatically after recordings. It seems to happen at startup, probably before mysql can come up. Here is more of the report which gives me clues. See attached pic.

There are a number of topics that address the backend starting up before the *network*
is up. They may help you verify that mysql is needed before the backend too. Look at
the systemctl cat command here to see yours:viewtopic.php?f=36&t=2764&p=14249&hilit=systemd#p14266
Note especially the "After=mysqld.service" line.